How to Navigate Persistent Acromegaly After Surgery

Surgery is often the first recommended treatment for acromegaly, a rare condition in which the pituitary gland at the base of the brain produces too much growth hormone — usually due to a noncancerous (benign) tumor.

Here’s what you should know about your options when surgery for acromegaly doesn’t resolve the condition.

Why Surgery May Not Be a Cure

“Some of these tumors are invasive and difficult to remove in their entirety,” says Lewis Blevins, MD, an endocrinologist at UCSF Health in San Francisco. “The surgeon just can’t get all of the tumor out, so they have persistent or active disease.”

A few factors can reduce the likelihood of a pituitary tumor being completely removed in surgery, says George Stamatiades, MD, PhD, an endocrinologist at Brigham and Women's Hospital in Boston:

• The tumor is large.
• The tumor extends into surrounding brain structures.
• The tumor is close to critical nerves or arteries.
• The neurosurgeon is inexperienced.

“Growth hormone-secreting tumors can sometimes be large or extend into areas that are difficult to safely access, such as the cavernous sinus, a space next to important nerves and blood vessels behind the eyes,” says Dr. Stamatiades. “In those cases, even a small amount of residual tumor can continue to produce excess growth hormone.”

It’s important to know that certain physical changes caused by acromegaly are likely to persist even if surgery is completely successful, says Dr. Blevins, possibly including bone enlargement, arthritis, and carpal tunnel syndrome.

“Anyone can have persistent symptoms and signs, even those that are cured,” Blevins says. In other words, a cure means that your hormone levels return to normal after your tumor is removed, not that your body will be completely free of signs of acromegaly.

Even if your acromegaly is cured, “Patients with acromegaly require ongoing monitoring for associated comorbidities,” says Stamatiades, which may include sleep apnea, high blood pressure, diabetes, cardiovascular disease, and colon polyps.

Persistent Acromegaly vs. Recurrence

After surgery to remove a pituitary tumor, you’ll undergo a series of blood tests to find out if the surgery was successful in curing your acromegaly. These tests may measure growth hormone as well as IGF-1, a hormone that your liver produces in response to growth hormone.

“IGF-1 is generally more reliable than growth hormone because growth hormone levels naturally rise and fall throughout the day,” says Stamatiades.

Depending on your pattern of test results, two kinds of unsuccessful results are possible: persistent acromegaly and recurrent acromegaly.

“Persistent acromegaly refers to continued evidence of disease immediately after surgery, indicating that excess growth hormone production was never fully controlled,” says Maria Fleseriu, MD, director of the Pituitary Center at Oregon Health & Science University in Portland.

But even if your initial test results appear successful, you may still have later tests that show a return of your acromegaly. “Recurrence occurs when a patient initially achieves remission or normal IGF-1 but develops active disease again months or years later,” says Dr. Fleseriu.

Compared with other conditions caused by pituitary tumors, Fleseriu says, people with acromegaly are less likely to experience recurrence after an initially successful surgery.

Treatment Options for Persistent Acromegaly

• Additional surgery
• Medications
• Radiation therapy

“Treatment is individualized,” says Stamatiades. “Our goal is not just to get the blood work into the normal range. We want to control the tumor, improve symptoms, prevent long-term complications, and help patients feel and function better in their daily lives.”

A second surgery for acromegaly may be an option in certain cases. “If the first surgeon was inexperienced, or if the surgeon thinks they can get the rest of the tumor,” then you may be a candidate, says Blevins. But if the remaining tumor is in an area where safely removing it would be difficult, another surgery may not be an option.

Because of the long-term risks associated with radiation therapy, Blevins says he typically reserves it for patients no younger than 45 to 50 years old.

Following Up With Your Endocrinologist

After surgery for acromegaly, the next steps will be guided by follow-up appointments with your endocrinologist.

Typically, Blevins says, patients get their blood levels of growth hormone and IGF-1 checked at 6 and 12 weeks after surgery. If your hormone levels are still elevated after 12 weeks, that likely means your surgery wasn’t completely successful and you have persistent acromegaly.

Also at 12 weeks, you’ll likely undergo magnetic resonance imaging (MRI) to look for any remaining pituitary tumor, says Fleseriu. This can help confirm a successful surgery or show why your hormone levels are still elevated.

If your hormone levels are borderline high or normal after 12 weeks, “We’ll presume that they’re probably okay but check them six months after surgery and then a year after surgery,” says Blevins. If your hormone levels are the same or lower in these follow-up tests, then you may not need any further treatment.

“Usually by three to six months, we’re starting someone on medical therapy if it looks like they have residual disease,” says Blevins, as indicated by persistently high hormone levels or a drop followed by a rise.

While blood tests are important and necessary to guide your treatment, they’re not the only thing your doctor should be paying attention to, says Stamatiades. “Just as importantly, we need to pay attention to how the patient is actually feeling,” he says. “We want to understand whether symptoms are improving, whether treatment is creating challenges, and whether there are any long-term complications that need attention.”